BYTEORDER(9) | Kernel Developer's Manual | BYTEORDER(9)

# NAME

bswap16, bswap32, bswap64, be16toh, be32toh, be64toh, htobe16, htobe32, htobe64, htole16, htole32, htole64, le16toh, le32toh, le64toh, be16enc, be16dec, be32enc, be32dec, be64enc, be64dec, le16enc, le16dec, le32enc, le32dec, le64enc, le64dec — byte order operations

# SYNOPSIS

#include <sys/endian.h>

uint16_t
bswap16(uint16_t int16);

uint32_t
bswap32(uint32_t int32);

uint64_t
bswap64(uint64_t int64);

uint16_t
be16toh(uint16_t big16);

uint32_t
be32toh(uint32_t big32);

uint64_t
be64toh(uint64_t big64);

uint16_t
htobe16(uint16_t host16);

uint32_t
htobe32(uint32_t host32);

uint64_t
htobe64(uint64_t host64);

uint16_t
htole16(uint16_t host16);

uint32_t
htole32(uint32_t host32);

uint64_t
htole64(uint64_t host64);

uint16_t
le16toh(uint16_t little16);

uint32_t
le32toh(uint32_t little32);

uint64_t
le64toh(uint64_t little64);

uint16_t
be16dec(const void *stream);

uint32_t
be32dec(const void *stream);

uint64_t
be64dec(const void *stream);

uint16_t
le16dec(const void *stream);

uint32_t
le32dec(const void *stream);

uint64_t
le64dec(const void *stream);

void
be16enc(void *stream, uint16_t host16);

void
be32enc(void *stream, uint32_t host32);

void
be64enc(void *stream, uint64_t host64);

void
le16enc(void *stream, uint16_t host16);

void
le32enc(void *stream, uint32_t host32);

void
le64enc(void *stream, uint64_t host64);

# DESCRIPTION

The bswap16(), bswap32(), and bswap64() functions return a byte order swapped integer. On big endian systems, the number is converted to little endian byte order. On little endian systems, the number is converted to big endian byte order.

The be16toh(), be32toh(), and be64toh() functions return a big endian byte ordered integer converted to the system's native byte order. The return value will be the same as the argument on big endian systems.

The le16toh(), le32toh(), and le64toh() functions return a little endian byte ordered integer converted to the system's native byte order. The return value will be the same as the argument on little endian systems.

The htobe16(), htobe32(), and htobe64() functions return an integer in the system's native byte order converted to big endian byte order. The return value will be the same as the argument on big endian systems.

The htole16(), htole32(), and htole64() functions return an integer in the system's native byte order converted to little endian byte order. The return value will be the same as the argument on little endian systems.

The be16enc(), be16dec(), be32enc(), be32dec(), be64enc(), be64dec(), le16enc(), le16dec(), le32enc(), le32dec(), le64enc(), and le64dec() functions encode and decode integers to/from octet stream on any alignment in big/little endian format.

# SEE ALSO

bswap(3), byteorder(3)

# HISTORY

The hto*() and *toh() functions first appeared in NetBSD 1.5. These were later ported to FreeBSD 5.0. These functions were originally introduced to handle PCI bus master devices that (via DMA) transfer little endian data even on big endian systems.

The encode/decode functions first appeared in FreeBSD 5.1. These were later ported to NetBSD 3.0 as a part of the uuidgen(2) support.

May 5, 2010 | NetBSD 7.2